Before the Ruth and Harold D. Uris Center for Education at the Metropolitan Museum of Art reopened last week, after a three-year overhaul, no one had any great hopes for it. Indeed, few people seem to have had an opinion about the project in the first place: To say that the architectural community remained silent in the matter would be a thunderous understatement.

The area occupied by the Uris Center, after all, had been a purely functional basement, rather like the museum’s unadorned service entrance over on 84th Street. It was a throwaway space to which the usual criteria of architecture and design did not seem especially relevant. The widespread acceptance of that opinion attests to the fact that the first Uris Center was so pallid and uninspired that one could hardly imagine that it might ever be otherwise.

Well, now it has been entirely transformed, and so successfully that you wonder how we could have tolerated the old space for 30 seconds, let alone 30 years. Kevin Roche John Dinkeloo and Associates, the architectural firm responsible for both the old space and the new, has used the pure power of design to effect this astonishing transition from a cavernous nothing to an eloquent, vital something, a space that lives and is a pleasure to inhabit.

Since the creation of the Met’s Petrie Court back in 1990, it has been a standing paradox of Roche Dinkeloo that they achieve far better results through neoclassicism than through the muscular modernism with which the firm was originally associated. The preeminent example of the latter is the 40-year-old Ford Foundation Building on First Avenue and 42nd Street. Largely as a result of that building’s critical success, the firm has served as the inhouse architects of the Metropolitan Museum since the mid-1970s, when the Met undertook its first major expansion in 60 years. In general, however, it is not a good idea — at least when a dozen or more discrete projects are involved — for an institution to surrender its architectural destiny to a single firm, especially when, as here, there is no need for a unified aesthetic.

No, the architectural history of the Met has always progressed in an ad hoc fashion and never more so than in the work that Roche Dinkeloo was hired to carry out. For the most part, the firm’s contributions have been resolutely mediocre: It is not merely old age that now requires that the Islamic galleries and the Michael C. Rockefeller Wing be fundamentally reconceived. It is also the feebleness of the designs. The architects’ American wing — which is also being recast at the moment — has fared a little better, but only because of its plants and abundant sunlight, rather than because of any felicity of design. Though the Temple of Dendur is entirely adequate to its function, that is the best that can be said for it.

But then came the Petrie Court, whose overriding aesthetic — delightfully and unexpectedly — was a late 20th-century reenactment of a mid-19th-century homage to the French Baroque. And, earlier this year, Roche Dinkeloo did themselves proud with the splendid new Greek and Roman Galleries, an improvement even on what McKim, Mead and White had originally nearly intended a century before.

All of which brings us to the new Uris Center, a hybrid of what might be called neo-modernism and contextual classicism. Formally, the overriding success of the new space is that it feels like a unified entity, charged with architectural cohesion. Its predecessor failed to achieve this, not through the usual reasons — the incoherent union of dissonant parts — but rather through a vapid and undisciplined spatial flaccidity. The new space achieves cohesion through the simplest means: unity of materials. At the entrance to the center, the Diane W. Burke Hall is covered in an elegantly matte Tennesee pink limestone that is carried throughout much of the center; the Rome-inspired bronze elevator doors, of a piece with those of the new Greek and Roman wing, also contribute to the overall elegance such that, for the first time, we think of this entrance area as an architectural zone in the first place.

Another major innovation is the decision to open the center up to a majestic corridor whose unfurling bays run straight down the middle of the space, with Carson Family Hall on your left and the new Nolen Library on your right. Flanking the entrance and continuing down the long corridor are Doric pilasters, made from the same material as the floors. Throughout, this limestone is interspersed with smooth and sumptuous blond maple wood along the walls, and both of these materials continue to be used once you reach the end of the hallways and head left or right for the auditorium or various classrooms. In addition, the corridor is graced with sheer glass windows and vitrines.

The most ravishing part of the new area, though, is surely the library, which, unlike the larger Watson Library, is open to all comers, rather than only to scholars, graduate students, and professionals. Its success is doubly impressive when you consider the drab little hole in the wall that it has replaced. Amid grayish-green carpets and strict, strikingly modern verticals and horizontals, this space is brightly lit by simple ranks of fluorescent light.

It must be said that the functionalism of some of the classroom spaces and the auditorium causes them to seem somewhat under-designed. But that does little to detract from the overall success of the new Uris Center, a destination that has been fundamentally upended and ennobled through the pure intelligence and skill of its design. It deserves what may be the highest praise that one can pay to any architectural act: Quite simply, one is happy to be there.

jgardner@nysun.com